The aim of the proposed research is to examine the effects of perceptual learning, or practice, on the vision of older adults. There are many older adults who exhibit no ocular pathology, but who do report visual problems. Psychophysical studies may help to determine the underlying basis for some of these problems, and may provide information for helping older persons overcome, or adjust to age-related visual declines. Long- term objectives are concerned with how practice might compensate for visual deterioration, and thereby enhance the quality of life for older adults. The first step toward achieving this goal is in the design and refinement of tasks which approximate the visual requirements of older adults in their everyday environments. The second step involves determining which types of training will be most beneficial. For example, it may be that higher order executive functions can compensate for age- related losses in the quality of sensory input. How early peripheral processes and higher-order processes interact, and change with age will aid in determining the limits of modifiability, the duration of improvements, and the extent to which improvements can be expected to generalize to other tasks. Studies aimed at improving visual performance in older adults should further our understanding of basic visual processes and thus benefit visual science as well as advance our knowledge of the aging process. Perceptual training will be conducted for 3 aspects of vision which are needed for everyday functioning: movement, peripheral vision, and spatial vision. Peripheral vision, used in the detection, localization, and recognition of objects, as well as motion perception, are significantly related to safe driving and mobility in general. Observers will receive training on tasks involving the presentation of targets in their periphery while other variables such as uncertainty, distraction, and task demands are changed. Masking effects will be studied to determine whether age declines on these tasks are occurring earlier in the visual system, or are due to higher order functions. Observers will also be trained on detection and discrimination between moving and spatial patterns. Transfer of training between tasks will also be measured. The basis for improvements will be analyzed in terms of changes in underlying physiological processes, the development of new cognitive strategies, and individual differences. Results will then be compared to existing models of visual perception in these three areas in an effort to arrive at a broader model of perceptual plasticity of the human visual system.